Lack of evidence of human papillomavirus-induced squamous cell carcinomas of the oral cavity in southern Germany

Viral DNA can be detected in some tumors by a sensitive PCR, but absence of ISH signals indicates that the HPV-attributable fraction is smaller than estimated from PCR positivity. p16INK4a/Ki-67 co-expression is detectable in a fraction of OSCC irrespective of the HPV status.